Combined sterilizer chambers and control



Oct. 22, 1968 J. B. KRAHE 3,407,029

COMBINED STERILIZER CHAMBERS AND CONTROL Filed Feb. 4, 1965 2 Sheets-Sheet 1 ICJ INVENTOR. JAMES B. KRAHE gpvfl a i FIG. 2 I M Oct. 22, 1968 J. B. KRAHE COMBINED STERILIZER CHAMBERS AND CONTROL 2 Sheets-Sheet 2 Filed Feb. 4, 1965 INVENTOR.

JAMES B. KRAHE BY WWW 3,407,029 COMBINED STERILIZER CHAMBERS AND CONTROL James B. Krahe, Erie, Pa., assignor to American Sterilizer Company, Erie, Pa., a corporation of Pennsylvania Filed Feb. 4, 1965, Ser. No. 430,445 3 Claims. (Cl. 21-93) This invention relates to sterilizers and, more particularly, to sterilizers suited for sterilizing large bulk amounts of goods.

In sterilizing goods in large bulk amounts in a single large chamber, the operator must start the gas cycle and then wait until the cycle is completed before he can take any of that load out or start another load. The cost of gas for sterilizing a small load in a large bulk sterilizer is identical to the cost for sterilizing a large load. This makes the cost of gas very high for small loads.

In selecting one of the dual gas sterilizers disclosed herein for a given installation, the user will first determine the maximum size of load he will be using. The dual gas sterilizer made up of two sterilizer units would then be provided with a total capacity to handle the maximum size load along with the improved control equipment disclosed herein.

The user will have a system that will enable him to handle his largest load by dividing the load between the two chambers and when operated as a dual sterilizer, both chambers will be operated from a single gas console. Although the chambers are operated by a single gas console control, each chamber has individual controls for the following functions: (a) humidity control; (b) chamber temperature control (jacket heat); vacuum pump system; (d) recorder for chamber pressure, vacuum, temperature indicating and recording; (e) fast exhaust system; (f) fresh air system.

When the user wishes to sterilize a load that can be handled with one chamber, he may set the controls so the chambers are isolated from each other. Thus, he has access to two independent sterilizers. Therefore, the user may then proceed to operate either chamber individually. The chambers may be used simultaneously for additional goods, under different operating conditons and/ or under different cycles.

-It will, therefore, be apparent that: The system is flexible and both chambers may be operated simultaneously to handle Large loads or individually for smaller loads. It may be necessary to make certain tests on sterilizer loads to com-ply with the requirements of the American Hospital Association (Biological Control) or the Food and Drug Administration (test samples for each load). When operating the two chambers as separate units, the user may take samples from either chamber. If he runs a large load using both chambers as one (dual gas), he need only take a sample from one chamber.

The controls for the two chambers as shown herein are indicated as manual controls by way of example; however, they could be designed as automatic controls by a person skilled in the art.

It is, accordingly, an object of the present invention to provide a sterilizer system made up of two chambers and control means whereby said chambers can either be operated simultaneously or individually.

Another object of the invention is to provide a sterilizing system which is simple in construction, economical to manufacture, and simple and etficient to use.

Still another object of the invention is to provide an improved sterilizing system.

A further object of this invention is to provide a sterilizing system made up of two separate individual chambers and two separate individual control systems and nited States Patent 0 3,407,029 Patented Oct. 22, 1968 ice a selector switch whereby one said control system may be controlled to operate both said chambers simultaneously from one said control or said two separate controls can operate said two separate chambers, respectively.

With the above and other objects in view, the present invention consists of the combination and arrangement of parts hereinafter more fully described, illustrated in the accompanying drawings and more particularly pointed out in the appended claims, it being understood that changes may be made in the form, size, proportions, and minor details of construction without departing from the spirit or sacrificing any of the advantages of the invention.

In the drawings:

FIG. 1 is a diagrammatic view of the mechanical elements of the sterilizing system;

FIG. 2 is a schematic view showing the valve system for the two chambers; and

FIG. 3 is a schemtic view of the electrical circuit for the system.

Now with more particular reference to the drawings, the system is made up of the control elements A and B, which are connected to and control the various functions of the chambers C and D. A gas selector switch S-6 shown in FIG. 3 is provided which controls the cycle of the two chambers as will hereinafter more particularly appear.

The chambers and control system are intended to carry out the sterilizing cycles, for example, such as cycles disclosed in patent application Ser. No. 414,721 filed Nov. 30, 1964, of 'Dr. James J. Shull and Robert S. Lloyd, and other sterilizing cycles familiar to those skilled in the art.

The chambers C and J) are of the conventional type of gas sterilizing autoclave that have a steam jacket around the outside as indicated in FIG. 2. The steam to the steam jacket of chamber C is provided by jacket heat valve V1 and steam to the jacket of chamber D is provided :by jacket heat valve V8. A 'humidity valve V2 connects moisture to the inside of the chamber C and the humidity valve V9 connects moisture to the inside of chamber D.

Vacuum suction valve V4 is connected to the inside of chamber C and vacuum suction valve V11 is connected to the inside of chamber D. Fast exhaust valves V5 and V12 are connected to the two chambers indicated and fresh air valves V6 and V13 connect fresh air to the inside of the two chambers in that part of the cycle. Valves V14 and V15, when open, connect the inside of chambers C and :D, respectively, to a source of sterilizing gas.

Referring to FIG. 3, it will be noted that the actuating members on gas control cycle switches S-3 and 8-5 are connected to a power source individually as two independent units when main power switch 8-1 is closed and when gas selector switch S6 is in the ON position indicated. In this position, the two chambers are independently controlled by gas control cycle switches S3 and S5, respectively.

Gas control switches S-2 and S4 control the power supply to the selector gas control cycle switches S3 and S5, respectively.

When the gas selector switch S6 is moved to the OF F position, the chambers C and D may be operated simultaneously by means of gas control cycle switch S3. Gas con trol cycle switch 8-5 will now be completely inoperative.

Switches T-l and T-2 are temperature control switches for chambers C and D, respectively. Recorders for the two chambers are indicated at REC. 1 and REC. 2. Vacuum pumps P1 and P2 are connected to evacuate the two chambers, respectively.

The operation of the chambers is as follows:

as dual units, the sequence of operation will be as follows:

(A) Turn main power switch 8-1 to ON position after terminals G and H have been connected to'a suitable source of power; for example, 110 volts A.C.

(B) Turn gas selector switch S6 to OFF position. This isolates gas control switch S3 and opens manifold valve V7.

(C) Move gas control switch S2 to ON position.

(D) Place the load of goods to be sterilized in each chamber and close and seal the doors to the chambers.

The cycle which is to be carried out will then be 'controlled by gas control elements A, which include gas control cycle switch S3 and Recorder REC. 1 andtemperature control switch T1. The identical cycle will be carried out in chambers C and D. The gas control cycle switches S3 and 8-5 are shown by way of example and these switches could be connected to carry out a cycle such as shown in patent application Serial No. 414,721 of Shull et al. The switches could be modified and suitable valving arrangements and other components provided to carry out any other suitable cycle.

An example of the cycle to be carried out herein will be outlined below:

(A) Turn :gas control cycle switch 8-3 to initial vacuum position (position 2), shown on control element A in FIG. 3. This opens vacuum suction valves V-4 and V-ll and also starts vacuum pumps P-1 and P-2.

(B) When the desired vacuum is reached in the chambers, turn the gas control cycle switch 8-3 to humidity position (3) on control element A. This opens humidity valves V-2 and V-9.

(C) When the desired humidity is reached in the chambers, turn the gas control cycle switch S3 to position (4). This will cause humidity valves V-2 and V-9 to close. After one hour humidity hold, open gas charging valves V14 and V15.

(D) When the desired gas pressure is reached in the chambers, close gas charging valve.

(E) After desired gas exposure, turn the gas control cycle switch S3 to the fast exhaust position (5). This opens the fast exhaust valves V-S and V-12.

(F) When pressure in the chambers reaches 4 p.s.i.-g., turn the gas control cycle switch 5-3 to the final vacuum position (6). This opens the vacuum suction valves V4 and V-ll and also starts the vacuum pumps P-1 and P-2.

(6) When the desired vacuum is reached in the chambers, turn the gas control cycle switch 5-3 to the fresh air position (7). This opens the fresh air valves V-6 and V-13.

(H) When the chambers reach atmospheric pressure, open the doors of the sterilizers and remove the load.

If the chambers are to be operated as separate units, the following sequence of operation will be carried out:

(A) Turn main power switch 5-1 to the ON position.

(B) Turn gas selector switch S6 to the ON position. This supplies power to gas control switch S4 and closes manifold valves V-7 which allows the chambers to be operated as separate units.

(C) The two chambers may now be operated as individual units by moving the gas control cycle switches S-3 and 8-5 in a manner to carry out the desired cycle of evacuation, humidification, and sterilizing.

It will be seen that the two sterilizers may be operated either as individual units by moving the gas selector switch S6 to the ON position or simultaneously when the selector switch is in the OFF position.

The foregoing specification sets forth the invention in its preferred practical forms but the structure shown is capable of modification within a range of equivalents without departing from the invention which is to be understood is broadly novel as is commensurate wit-h the appended claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A control for sterilizers comprising a first chamber and a second chamber,

a plurality of first valve means connected to sources of vacuum and sources of-gas and to said first chamber for connecting said sources of vacuum and sources of gas to said first chamber,

a plurality of second valve means connected to sources of vacuum and sources of gas and to said second chamber for connecting said sources of vacuum and sources of gas to said second chamber,

a first cycle switch connected to said first valve means,

a second cycle switch connected to said second valve means,

a selector switch,

a source of power,

said selector switch having a first position and a second position,

said selector switch having means to connect said first cycle switch to said second valve means when said selector switch is in said first position whereby said chambers may be both operated simultaneously from said source of power from said first cycle switch,

said selector switch having means thereon connecting said first cycle switch to said source of power and connecting said second cycle switch to said source of power independent of each other when said selector switch is in said second position whereby said chambers can each be operated independent of the other through said first cycle switch and said second cycle switch, respectively.

2. The control recited in claim 1 wherein a source of gas is provided,

gas charging valves :are provided connected to said chambers for connecting said chambers to said source of gas,

and said selector switch has means thereon connecting a source of power to said charging valves when said selector switch is in said first position.

3. The control recited in claim 1 wherein said cycle switches each have a single movable contact and a plurality of fixed contacts,

said selector switch has a plurality of first fixed contacts, a plurality of second fixed contacts, and a plurality of movable contacts,

some of said fixed contacts on said first cycle switch being connected to said first valve means and to a corresponding fixed contact on said selector switch,

some of said movable contacts on said selector switch being connected to said second valve means,

said first fixed contacts on said selector switch being connected to said fixed contacts on said first cycle switch,

some of said fixed contacts on said second cycle switch being connected to said second valve means,

some of said second fixed contacts on said selector switch being connected to said second valve means.

References Cited UNITED STATES PATENTS 3,338,663 8/1967 Beecher et al 2l98 MORRIS O. WOLK, Primary Examiner.

BARRY S. RICHMAN, Assistant Examiner. I 

1. A CONTROL FOR STERILIZERS COMPRISING A FIRST CHAMBER AND A SECOND CHAMBER, A PLURALITY OF FIRST VALVE MEANS CONNECTED TO SURCES OF VACUUM AND SOURCES OF GAS AND TO SAID FIRST CHAMBER FOR CONNECTING SAID SOURCES OF VACUUM AND SOURCES OF GAS TO SAID FIRST CHAMBER, A PLURALITY OF SECOND VALVE MEANS CONNECTED TO SOURCES OF VACUUM AND SOURCES OF GAS AND TO SAID SECOND CHAMBER FOR CONNECTING SAID SOURCES OF VACUUM AND SOURCES OF GAS TO SAID SECOND CHAMBER, A FIRST CYCLE SWITCH CONNECTED TO SAID FIRST VALVE MEANS, A SECOND CYCLE SWITCH CONNECTED TO SAID SECOND VALVE MEANS, A SELECTOR SWITCH, A SOURCE OF POWER, SAID SELECTOR SWITCH HAVING A FIRST POSITION AND A SECOND POSITION, SAID SELECTOR SWITCH HAVING MEANS TO CONNECT SAID FIRST CYCLE SWITCH TO SAID SECOND VALVE MEANS WHEN SAID SELECTOR SWITCH IS IN SAID FIRST POSITION WHEREBY SAID CHAMBERS MAY BE BOTH OPERATED SIMULTANEUSLY FROM SAID SOURCE OF POWER FROM SAID FIRST CYCLE SWITCH, SAID SELECTOR SWITCH HAVING MEANS THEREON CONNECTING SAID FIRST CYCLE SWITCH TO SAID SOURCE OF POWER AND CONNECTING SAID SECOND CYCLE SWITCH TO SAID SOURCE OF POWER INDEPENDENT OF EACH OTHER WHEN SAID SELECTOR SWITCH IS IN SAID SECOND POSITION WHEREBY SAID CHAMBERS CAN EACH BE OPERATED INDEPENDENT OF THE OTHER THROUGH SAID FIRST CYCE SWITCH AND SAID SECOND CYCLE SWITCH, RESPECTIVELY. 